Clear-cell sarcoma is a very rare tumor, and is almost always associated with tendons or aponeuroses or is metastatic from other organs. Sporadic cases only have been reported involving primarily the bone or extending from soft tissues to surrounding bones. To our knowledge, the ilium has not been previously reported as the primary site for clear cell sarcoma.

We report a rare case of Primary clear cell sarcoma involving right ilium region in a 18-year-old boy presented with a painful swelling over right ilium and limp on right lower limb of ten month duration. He was initially suspected having tuberculosis based on clinicoradiological evaluation and diagnosis of primry clear cell sarcoma could be established on histopathology. Patient was treated with partial excision of the ilium, the remaining ilium was fused with sacrum. Stabilization was achieved with a cortical autograft harvested from the right fibula and fixation with a titanium plate.

The patient had no local recurrences but the plate holding ilium to sacrum broke and was removed in the subsequent surgery after which he developed Trendelenberg’s gait.

Abstract. Background. Schwannomas are slow-growing, benign tumours normally originating from the Schwann cells of the nerve sheath. Intraosseous schwannoma accounts for 0.175% of primary bone tumours and extremely rare especially outside the axial skeleton. Monoclonal gammopathy has been associated with soft tissue schwannomas but never with the intraosseous variety. Presenting problem. A 55-year-old woman with a background of monoclonal gammopathy of undetermined significance (MGUS) presented with a 2-year history of right thigh pain. CT scan showed a well defined, lytic lesion with a thin peripheral rim of sclerosis in the midshaft of the femur. MRI displayed a hyperintense, well marginated and homogenous lesion. Definitive diagnosis was made based on the classical histopathological appearance of schwannoma. Clinical management. We managed our patient with local curettage and prophylactic cephalomedullary nailing on the basis of a high mirel score. Discussion. Intraosseous schwannomas are poorly understood but most commonly reported in middle-aged women. Radiologically, their differential diagnosis includes malignant bone tumours, solitary bone cysts, aneurysmal bone cysts and giant cell tumours. As a result, they are usually diagnosed incidentally on histology. Although malignant transformation is possible in soft tissue schwannomas, all intraosseous schwannomas reported to date have been benign. This case demonstrates the importance of suspecting intraosseous schwannoma as a differential diagnosis for lytic bone lesions to avoid the overtreatment of patients. We also highlight monoclonal gammopathy of undetermined significance as a potential risk factor for a poorly understood disease and make recommendations about the appropriate management of these lesions. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Introduction and Aims: Rapidly progressive lytic lesions of the calcar develop under the collar of cemented titanium femoral stems inserted in our unit. Progression of the defects slowed after reaching a critical size. Biopsies showed granulomatous lesions with polyethylene particles and multi-nucleate giant cells. The aim of the study was to determine the natural history of these lytic lesions. Method: We developed a finite element analysis model. We determined the parameters of the FEA model, to reflect the geometry and physical characteristics of the prosthesis-bone construct and also factored in both loading and non-loading parameters. We also determined the characteristics of titanium and cobalt-chrome prostheses. Results: We determined from the FEA model that there is some vertical displacement of the collar relative to the calcar-cement construct. This displacement is larger in the titanium than the cobalt-chrome model. The magnitude of the displacement is larger than the average polyethylene particle size. On loading and non-loading this displacement allows the development of a pump action, thus concentrating polyethylene particles under the collar of the prosthesis and leading to the granulomatous lytic lesions. The FEA studies demonstrated that the pumping action of the collar became less efficient, but did persist, as the lytic lesions increased in size. Conclusion: We have explained the development of calcar lytic lesions under the collar of femoral stems. A pump action is present in loading and non-loading phases, sucking in polyethylene particles and allowing granulomatous lesions to form. We recommend caution when using collared femoral prostheses, more so titanium than cobalt-chrome, because of the development of calcar lytic lesions

Introduction. Stryde® lengthening nail has been recently withdrawn because of concerns about osteolysis and other bone lesions that have been observed early after implantation. The present study analyses the incidence and features of these bone lesions in our patients. Materials and Methods. This is a retrospective review of a series of patients from two centres specializing in limb reconstruction. Inclusion criteria was a history of surgery with Stryde® lengthening nail with more than one year follow-up available. All postoperative x-rays were and clinical notes were reviewed. Results. 36 patients with 75 bone segments were included. 11 (30.5%) patients and 32 (42.6%) bone segments were without any lesion. In 3 (8.3%) patients and 3 (4%) segments, osteolytic lesions only were noticed. 11(30.5%) patients and 14 (18.6%) segments had combined lytic lesions and periosteal reaction or cortical thickening. 12 (33.3%) patients and 26 (34.6%) segments developed only periosteal reaction or cortical thickening. 54.8% of patients with bilateral nailing had bilateral lesions. 52% of the patients with bone lesions reported late onset of pain after the completion of the lengthening. The average earliest interval that any of the lesions was noticed was 10.2 months post-surgery. Conclusions. Patients with Stryde® nails should be monitored clinically and radiologically at regular intervals until removal. The early failure and withdrawal of Precise Stryde® nail, is a significant event in the field of limb reconstruction; this study adds useful data to the growing pool of published data related to the this event

Introduction: Mirels scoring system is a recognised method of assessing the risk of fracture in metastatic bone disease (MBD) based on radiological and clinical risk factors. Although reproducible, there are overlaps in the outcome of the scores. Aim: The aim of this study is look at the association between the tumour volume and ratio, and the incidence of pathological fracture. Method: Mirels score was calculated retrospectively from the patient notes. X-rays were scanned and analysed using the IMAGICA program. All tumours were measured twice on two views to the closest 0.1mm. The average of the two readings were used for the final calculations. Tumour volume was measured using 3 axis readings on the anteroposterior (AP) and lateral views of the tumour. The AP and lateral width of the tumour and the long bone shaft was measured to obtain the AP and Lateral Tumour Ratio (APTR and LTR respectively). Results: 58 patients were admitted in 2003 with suspected primary or MBD of a long bone. 50 patients were included. 28(56%) were male. Average age was 69.2years (range 10–98years). 6(12%) patients had a lytic lesion with no fracture and 18(36%) with pathological fracture. We were unable to measure Mirels score due to poor documentation. Patients with lytic lesion and no fracture had lower APTR and LTR, 0.88 and 0.85 respectively compare with the patients with lytic fractures (APTR 0.98 and LTR 0.91). This trend was not seen in tumours with sclerotic and mixed features. The average tumour volume was higher in the patients with lytic lesion and associated fracture than those with no fracture, 27.3 and 20.7cm³. 17(85%) of the lytic lesions, with volume larger than 10 cm³ had pathological fracture. Conclusion: The fracture rate is higher in presence of larger tumour with higher AP and lateral tumour ratio. A single measurement of the tumour volume may be more appropriate in the assessment of a lytic lesion for pathological fracture

We have previously reported on early lytic lesions occurring when collared titanium prostheses are used. Previous finite element analysis studies (FEAs) showed that lytic lesions of the calcar were due to concentration of polyethylene wear particles under the collar by a ‘pumping action’. Further follow-up of these calcar lytic lesions showed that their rate of increase in size progressively slowed down. Further FEAs were performed to determine why this was so. An FEA mesh construct was developed, incorporating the new parameters of no contact between the collar and the calcar bone. A mechanical model to determine displacement parameters was also developed. These FEA studies demonstrated that the pumping action of the collar became less efficient as the size of the lytic lesions increased. This led to less concentration of polyethylene particles under the collar and fewer granulomatous reactions. The change in the proximal prosthesis-cement-bone construct may lead to cement mantle deterioration and earlier failure. We still recommend caution when a collared prosthesis is used, and the material and geometry of the prosthesis remain important

Salmonella osteomyelitis occurs infrequently in children without a sickle cell disease, and its subacute form is rare. Diagnosis is often delayed because its slow onset, intermittent pain and it can be confused with bone tumors. An otherwise healthy 13-year-old boy was admitted from another center in order to discard bone tumor in proximal tibia, with compatible radiologic findings. There was no history of trauma or previous illness. Twenty days ago, he had flu symptoms and myalgia. On the physical examination the child was feverless, showed increased heat over his left knee, considerable effusion and painful restriction of movement. Inflammatory laboratory results revealed erythrocyte sedimentation rate 46mm/h and C-Reactive protein, 11,2 mg/L. Radiographs revealed a lytic lesion localized in the proximal metaphysis and epiphysis. The MRI showed an area of edema around the lytic lesion and surrounding soft tissues. Images supported the diagnosis of subacute osteomyelitis, (Brodie abscess). Empirically, intravenous cefuroxime was started. Forty-eight hours post admission, the patient underwent abscess surgical debridement, washout and cavity curettage. Samples were sent for cytology, culture and sensitivity and acid fast bacilli culture and sensitivity. Collection´s count cell was 173.000/ L white cells. Collection´s culture revealed Salmonella B sensitive to ciprofloxacin. Stool culture did not yield any growth. Intravenous cefuroxime was administered during 10 days. The patient responded well as evidenced by clinical and laboratory improvement He was discharged with his left leg immobilized in a cast during 1 month and treatment was completed with oral ciprofloxacin 500mg /12 h during 2 months. The patient had full range of knee motion after 2 months. Last reviewed, after two years of the income, he was completed recovered, and the radiograph showed bone healing without physeal neither damage nor limb leg discrepancy. The most effective therapy of a confirmed salmonella osteomyelitis is a combination of radical operative intervention and targeted intravenous antibiotics as in our case. Faced with a subacute osteomyelitis, we have to remember that it may mimic bone tumors. We highlight the isolation of Salmonella B in a patient without sickle cell disease

Good short-term results with Mt Blanc uncemented acetabular cups have been previously reported. However, in the medium term, we have observed acetabular loosening related to large granulomatous lytic lesions. To determine the cause of the polyethylene load causing the granulomatous lytic lesions, we subjected six explanted Mt Blanc acetabular cups to retrieval analysis. We also reviewed the literature on polyethylene locking mechanisms in uncemented metal-backed cups and on the deformability of metal-backed cups. We subjected the retrieved cups to stereo-photographic analysis and to dye penetration and surface scanning electron microscopy techniques. We demonstrated severe polyethylene wear and particle generation on the back surface of the polyethylene insert. This was due both to two-body sliding wear, as characterised by surface deformation and delamination of the polyethylene, and to three-body abrasive wear, as characterised by surface roughness and embedded titanium particles. The literature confirmed that the locking mechanism of the Mt Blanc cup was particularly poor and the deformability greater than in other cups tested. This confirmed the wear patterns on the back-surface of the polyethylene liner. We caution against the use of uncemented cups that have poor locking mechanisms for the polyethylene liners and those that deform excessively. The combination of poor locking mechanisms and titanium shells is especially dangerous

Fibrous dysplasia is a genetic not hereditary disease of the skeleton, most frequently located at the femoral bone. The extension and the radiographic morphology of the femoral lesion are variable, and the prognosis is unpredictable. The purpose of this study is to propose a radiographic classification of the femoral lesion, related to the prognosis and the natural history of the disease. The authors reviewed the radiographic examinations of 25 patients affected by fibrous dysplasia of bone with femoral involvement, who were followed-up at least two years after diagnosis. Eleven patients had bilateral localization of the disease, for a total of 36 affected femurs. A radiographic classification of the femoral lesion was proposed based on the localization, the extension and the type of the lesion. The authors classify the femoral lesions as lytic, lytic with surrounding sclerosis, lytic and sclerotic, sclerotic and complex. They observed a prevalence of the lytic lesions and involvement of the proximal part of the femur. Many lesions (40%) expanded with age, and the sclerotic component also increased. The lytic lesions worsened with age, causing severe deformity of the femur. However the mostly sclerotic lesions turned out to be stable at follow-up. The worsening of the lesion was not related to the sex of the subjects; 77% of the worsened lesions were observed in patients younger than 20 years of age, while 66% of the stable lesions were found in patients older than 20 years. In conclusion, this study demonstrated that the prognosis of the femoral lesion in fibrous dysplasia is related to the type of lesion, as per the radiographic classification here in described. Prognosis is also related to the age of the patient and the presence of a sclerotic component, which suggested a greater stability of the lesion

A fifty year old lady with history of rheumatoid arthritis (RA) for 24 years and COPD for 10 years was admitted for investigation of persistent chest infection and for the control of RA flare-up. She was on Sulphasalazine, NSAIDs and had completed a course of gold injections and on admission started on methotrexate, folic acid, Calcium, bisphosphonates and alendronate. Urinanalysis was positive for Bence Jones’ Proteins (BJP). Four days after admission patient developed spontaneous pain in the right thigh with inability to move the right leg. Radiographs showed a supracondylar femoral fracture through a lytic lesion, which was stabilised with a Distal femoral nail. At surgery bone quality of right femur was found to be very poor. Radiographs of the left femur showed a lytic lesion in the subtrochanteric region, which was stabilised prophylactically with a Proximal Femoral Nail. Histopathological examination of the marrow reamings from right femur showed no neoplastic changes and from left femur showed occasional plasma cells. 24 hour urinanalysis showed BJP of 0.22g/hour and protein electrophoresis showed monoclonal antibodies. Bone marrow biopsy was performed which showed only reactive cells. A week later 24 hour urine BJP was down to 0.13g/hour. At three weeks, symptoms of RA were under control and the protein electrophoresis showed no monoclonal banding. Chest infection resolved with appropriate antibiotics. Computerised Tomography of chest showed bronchiectasis with no evidence of neoplasm. Discussion: In acute stages of RA there is an increase in antibodies production that may present as positive for monoclonal antibodies on electrophoresis and by the same reason urine may be positive for BJP. The spontaneous fracture in this case could be due to severe reactive osteoporosis confounding the clinical picture of active RA. Without clear evidence of myeloma or plasmacytoma, instituting chemotherapy may lead to further complications in patients with RA

Peri-prosthetic bone loss may contribute to aseptic loosening after THA. The aims of this randomised controlled trial extension study were to study the effect of pamidronate therapy on Peri-prosthetic bone mineral density (BMD) and Peri-prosthetic osteolysis over 5 years after primary THA. 50 patients were enrolled in the study in 1998. All received a hybrid THA (Ultima-TPS stem, Plasmacup) for osteoarthritis. Subjects were randomised to receive either 90mg of pamidronate or placebo by intravenous infusion on the 5. th. post-operative day. At 5 years 36 patients (41 Hips: placebo n=21, pamidronate n=20) returned for measurement of BMD and clinical and plain radiographic assessment. Five patients had died and nine had withdrawn from the study. The effect of pamidronate in maintaining femoral bone mass in the region of the calcar previously reported at 2 years was maintained at 5 years (Gruen zone 6 pamidronate versus placebo ANOVA P=0.038; Gruen zone 7 ANOVA P=0.048). No differences in pelvic BMD were found between treatment groups at 5 years. Harris hip scores used to evaluate clinical outcome did not show any significant difference between the 2 groups over the 5-year period. (Mann Whitney p> 0.05). Isolated expansile osteolytic lesions were identified on AP radiographs of the hip at 5 years in 4 patients (2 placebo, 2 pamidronate; P> 0.05). One patient had a 5x9mm lytic lesion in the region of the femoral calcar, and 3 patients had pelvic lytic lesions in the region of the acetabular dome (largest measuring 20x10mm). Single-dose peri-operative pamidronate therapy preserves femoral calcar bone mass over a 5 year period after THA. However, although the number of subjects with osteolysis is small, we have seen no difference in the rate of osteolytic lesions between treatment groups. Long term study of this patient group is required to examine the rate of aseptic loosening between the treatment groups

Chronic calcaneal osteomyelitis is a rare and not usually part of the initial differential diagnosis of pseudotumoral calcaneal lesions. Presentation of surgical and functional outcomes of a case of a total calcanectomy. This can be seen as a foot rescue alternative in patients with chronic calcaneal osteomyelitis. We present the case of a 60 year- old patient with complaints of diffuse and intermittent pain in the left heel with 3 years of evolution. Radiographically, lytic lesion image sclerotic edges that covers the entire calcaneus, with preservation of cortical. MRI shows holo-calcaneal lesions compatible with tumor, infectious or inflammatory lesion. A biopsy is inconclusive. Negative microbiology results. Regular analytical study. It was decided to conduct a total calcanectomy. Procedure took place without complications. Patient still skin healing phase, without any pain complaint. It presents iconographic material made if and procedure. The total calcanectomy is an alternative procedure to transtibial amputation in patients with chronic calcaneal osteomyelitis

With cementless porous-coated acetabular replacements, extensive bone loss can occur without effecting implant stability. As a result, the surgeon is frequently faced with re-operating on a well-fixed cementless acetabular component with osteolysis and must decide whether or not to remove a well-fixed porous coated socket. A classification system and treatment algorithm has been developed to aid in management decisions regarding re-operation for polyethylene wear and pelvic osteolysis. Cases are classified into one of 3 possible categories depending on the radiographic stability of the porous coated shell and the ability to replace the polyethylene liner. Type I case; stable porous coated shell, liner replaceable; Type II case; socket stable, liner not replaceable;. Type III case; socket loose, not osseointegrated. Treatment Algorithms - Retain well-fixed shell in Type I cases and replace the liner. Debride accessible lytic lesions and graft with allograft chips. Remove the well-fixed shell in Type II case. Assess defect once the shell is removed. Reconstruction based on the bony defect present. The vast majority can be revised with a larger porous coated socket. Remove loose socket in Type III cases. Assess defect and reconstruct based on the defect. There is a greater need for more extensive grafting and the use of reconstruction rings with Type III cases. This treatment algorithm has helped the authors successfully evaluate and treat a large series of patients with polyethylene wear and pelvic osteolysis in association with porous coated acetabular components. The stability of the acetabular component and appropriate knowledge of the implant are important factors that impact surgical management

Reoperation on the acetabular side of the total hip arthroplasty construct because of acetabular liner wear with or without extensive osteolysis is the most common reoperation performed in revision hip surgery today. The options of revision of the component or component retention, liner exchange (cemented or direct reinsertion) and bone grafting represent a classic surgeon dilemma of choices and compromises. CT scanning is helpful in determining the size and location of osteolytic lesions. My preference is to retain the existing shell when possible especially when there are large osteolytic lesions but where structural support is maintained. The advantages of complete revision are easy access to lytic lesions, ability to change component position and the ability to use contemporary designs with optimal bearing surfaces (for wear and dislocation prevention). The disadvantage is bone disruption including pelvic discontinuity with component removal (less so with Explant Systems) and difficult reconstructions due to excessive bone loss from the osteolytic defects (sometimes requiring cup cages). The advantage of component retention is that structural integrity of the pelvis is maintained and in general, a higher quality polyethylene is utilised. For large lesions I use windows to debride and bone graft the lesions. If the locking mechanism is inadequate, cementing a liner, including a constrained liner in some cases, that has been scored in a spider web configuration provides durable results at 5-year follow-up. The downside to liner exchange is potential instability. We immobilise all liner exchange patients postoperatively

Prevention: Many periprosthetic femur fractures may be prevented by: good patient follow-up; timely reoperation of lytic lesions if radiographs suggest fracture risk; prophylactic use of longer stemmed implants or strut grafts to bypass cortical defects at revision surgery. Treatment: Periprosthetic fractures can be treated using an algorithmic approach based on the Vancouver classification system. Fractures of greater or lesser trochanter (Type A): nonoperative treatment if displacement acceptable and if not associated with lysis; operative treatment if displacement unacceptable or associated with progressive lysis. Fractures of distal femur well distal to implant (Type C): treat as any other femur fracture, usually operatively; fixation options: plate/retrograde nails. Fractures around the implant or at its tip (Type B): these fractures almost always require surgery. Nonoperative treatment is associated with high rate of malunion, nonunion, poor results. Treatment is according to fixation status of implant and bone quality. Well-fixed stem (Type B1): ORIF with cable plate and/or strut grafts; or with locking plate and minimally invasive biologic technique. Loose stem (Type B2 and Type B3): revise implant to long stem; usually use uncemented distally-fixed implant; occasionally long cemented stem (avoid cement extrusion). In most cases we favor use of a modular fluted tapered stem which provides axial and rotational stability by fixation distal to the fracture. Principles: obtain fracture stability, implant stability, and optimise conditions for bone healing (use bone grafts, don't strip periosteum)

Introduction: Metastases in multiple myeloma are typically lytic and when non-union occurs it is usually atrophic. Methods: We report a lady of 67 years who was diagnosed with myeloma 9 years previously. She presented with a sudden onset of pain in her right forearm. Plain radiographs demonstrated a lytic lesion typical of multiple myeloma with an undisplaced pathological fracture in her right ulna. The fracture was treated in a short arm cast for 6 weeks and then by mobilisation. The underlying bone deposit was treated subsequently by external beam irradiation. Results: Nine months later she was re-referred to the orthopaedic oncology service with marked forearm pain particularly on rotation. Radiographs demonstrated a hypertrophic non-union of the pathological fracture with a typical elephant’s hoof appearance. The fracture was stabilised using a Foresight ulnar nail (Smith and Nephew, Warwick, UK). Discussion: Whilst non-unions in metastatic malignancy are typically atrophic, just occasionally hypertrophic non-unions can occur. Management principles remain the same with stabilisation of the entire bone and early mobilisation being appropriate

With cementless porous-coated acetabular replacements, extensive bone loss can occur without affecting implant stability. As a result, the surgeon is frequently faced with re-operating on a well-fixed cementless acetabular component with osteolysis and must decide whether or not to remove a well-fixed porous coated socket. A classification system and treatment algorithm has been developed to aid in management decisions regarding re-operation for polyethylene wear and pelvic osteolysis. Cases are classified into one of 3 possible categories depending on the radiographic stability of the porous coated shell and the ability to replace the polyethylene liner. Type I case; stable porous coated shell, liner replaceable; Type II case; socket stable, liner not replaceable; Type III case; socket loose, not osseointegrated. Relative Contra-indications for Liner Exchange – Type II Case - Malpositioned socket, Severely damaged shell or lock detail (consider cementing shell in place), Poor track record of the implant, Highly crosslinked polyethylene liner of adequate thickness not available, Ongrowth (as opposed to ingrowth) fixation surface. Treatment Algorithm. Type I Case: Retain well-fixed shell in Type I cases and replace the liner. Debride accessible lytic lesions and graft with allograft chips. Type II Case: Remove the well-fixed shell in Type II case. Assess defect once the shell is removed. Reconstruction based on the bony defect present. The vast majority can be revised with a larger porous coated socket. Type III Case: Remove loose socket. Assess defect and reconstruct based on the defect. There is a greater need for more extensive grafting and the use of reconstruction rings with Type III cases. This treatment algorithm has helped the authors successfully evaluate and treat a large series of patients with polyethylene wear and pelvic osteolysis in association with porous coated acetabular components. The stability of the acetabular component and appropriate knowledge of the implant are important factors that impact surgical management

Clear cell meningioma is a rare subtype of meningiomas graded II according to the World Health Organisation classification. In spite of its benign appearance, clear cell meningioma has an aggressive behaviour and it is characterized by its inordinately tendency to metastasize. The purpose of this study is to discuss the clinico-pathological features of this subtype of meningiomas as well as the metastatic pathways. We wish to report a rare case of a clear cell meningioma metastasizing to the sacrum 17 years after the removal of the primary tumour. A 26 year-old man was referred to our centre for low back pain related to a lytic lesion of the sacrum. He had a history of a tumour of the forth cervical vertebra that was removed when he was 9 year-old. CT scan revealed an osteolysis of the entire sacrum invading the intrapelvic organs and the sacro-iliac joints. Open biopsy revealed a clear cell meningioma. That was the same pattern of the tumour removed 17 years earlier. Chest CT showed lung metastases. The patient was managed conservatively by palliative radiation therapy. One year later, he experienced improvement of pain and walk. The mass was stable. Clear ell meningioma is an aggressive tumour with a potential to spread via cerebro-spinal fluid and haematologically. Patients with such a tumour should be closely followed for a long time

Introduction: Pigmented villonodular synovitis is an uncommon, benign, proliferative, neoplastic process of the synovial membrane presumed to be of histiocytic origin and is likely to cause diagnostic dilemma. We present 4 cases with varied presentations in the form of increasing groin pain, inguinal mass, co-existing osteoarthritis which were subsequently confirmed to have PVNS. Methods and results: Clinical records and imaging modalities of 4 patients with histologically confirmed Pigmented villonodular synovitis of the hip, accrued from Scottish Bone Tumour Registry between 1969 and 2000 were reviewed. Discussion: PVNS of the hip is an important differential diagnosis when osteoarthritis is associated with atypical clinical picture or lytic lesions. Although it remains confined to the joint, soft tissue masses extending beyond the capsule in to retroperitoneum or anterior and posterior aspects of hip have been reported as shown here. Radiographs in early stages are normal or include a concentric joint space narrowing. MR is an important non-invasive modality for surgical planning and to define the size and extent of the lesion, recurrence, delineating between synovial proliferations and periarticular or intra-abdominal organs. The role of arthroscopy, both diagnostic and therapeutic, is rapidly emerging, although, it has its own limitations. A carefully performed total excision often prevents recurrence as can be seen in this series

We present a case of osteolytic lesion in Gruen Zone 2, 3 in a six-month post-operative cemented THR initially diagnosed as early loosening-?Septic. Investigations and biopsy revealed metastatic renal cell carcinoma. A 79 year old gentleman had a Left cemented THR and was symptom free post-operative. Six months later he had pain in the left groin and thigh. Examination revealed painless hip movements. X-ray showed lytic area in zone 2 and 3. ESR -90 mm and CRP – 50 mg/dl. Hip aspiration excluded sepsis. Bone scan showed increased uptake of left femoral shaft, right scapula and L1 vertebra. Bone chemistry, renal & liver Assay and tumour markers were normal. Open biopsy showed erosion of lateral cortex, with friable soft tissue mass with profuse bleeding. Histopathological report showed classical clear cell renal cell carcinoma. CT abdomen and chest revealed multiple nodules in lung fields, multiple nodules in liver, mass in both kidneys consistent with Renal cell carcinoma, multiple skeletal lytic lesions. Patient was referred to oncologist for palliative treatment. DISCUSSION: In case of osteolytic erosive lesions at cement bone interface, the possibility of metastatic lesions should be considered. In old age groups Biopsy is recommended to exclude malignancy after exclusion of septic and aseptic loosening and abdominal ultrasound to exclude primaries